Internal-combustion engine.



6 SHEETS-SHEET 1.

PATENTED JAN. 27, 1903.

ZIP".

C. E. DAWSON.

APELIOATION FILED DEG. 10, 1900.

INTERNAL COMBUSTION ENGINE.

No MODEL.

we Nonms Finns co.. mom-uwe., wAsMlNp'roN. n. c

PATENTED JAN. 27,1903.

o. E. EAWsoN. INTEENAL GOMEUSTION ENGINE.

APPLIOATIN FILED DEO. 10l 1900.

6 SHEETS-SHEET 2.

N0 MODEL.

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1N: nonms creas co., wom-urne.. wAsm PATENTED JAN. -2'7, 1903.

. C. E. DAWSON.

INTERNAL GoMEUsTIoN ENGINE.

APPLICATION IILLI) DEO. 10, 1900.

6 SHEETS-SHEET 3 rave N0 MODEL.

E norms Petras co.. PNOTQLITHO., wAsHlNYoN. n. c.

NO MODEL.

EATENTED JAN. 27, 1903. C. E. DAWSON. INTERNAL COMBUSTION ENGINE.

APLIQATION FILED DEO. l0, 1900.

8 SHEETS-SHEET 9:.

PATENTED JAN. 2v, 190sL 6 SHEETS-SHEET 5.

o. E. DAWs0N. INTERNAL GOMEUSTION ENGINE.

APPLICATION FILED DEO. 10, 1900.

N0 MODEL.

1n: Noams vzzs no.. PNoYuLlwo.. wAsHlNoTom o. c.

No. 719,199. f PATENTED JAN. 27., 1903.

C. E.l DAWSON.

INTERNAL GOMBUSTION ENGINE. 1

APPLIOATION FILED DBO. 1o, 1900. 4 Bo 110ML. 6 sums-SHEET 6.

YM: Nonnvxs PETERS co, PNDmLITNo., wAsHmnmN, D. c

llrTTTEnn ETETEs PATENT EETCE.

CHARLES ERNEST DAWSON, OF HYTIIE, ENGLAND.

INTERNAL-COMBUSTION ENGINE.

SPECIFICATION formingpart of Letters Patent No. 719,199, dated January27, 1903.

Application filed December 10,1900. Serial No. 39,427. (No model.)

To a/ZZ Lch/0771, t Hefty concern:

Be it known that I, CHARLES ERNEST DAw- SON, engineer, a subject of theKing of Great Britain and Ireland, residing at The Villa, Hythe, nearSouthampton, England, have invented certain new and useful Improvementsin Internal-Combustion Engines, (for which I have made application forpatent in Great Britain, No. 9,055, and dated May 16, 1900,) of whichthe following is a specification.

My invention relates to internal-combustion engines in which light orheavy oils are used, and has for its object to provide a simple andreliable engine of the two-strokecy cle type.

My invention is also designed to enable the engine to be worked with acharge free from spent gases and at the same time to prevent part of theexplosive charge from following the exhaust-gases, and so being lost.

My invention consists in attaching in any suitable manner to the mainpiston a displacing-piston of suitable area, which discharges throughordinary non-return valves into two reservoirs, each of considerablecapacity. These reservoirs both communicate with a common passageleading tothe combustionspace of the cylinder, but are eachindependently closed by valves so controlled that the contents of one otthe reservoirs are discharged through the cylinder when the pistonpasses exhaust-ports in the cylinder-walls and the pressure has fallensufficiently, thus thoroughly scavenging the cylinder. The springcontrolling the valve which closes the second reservoir is soproportioned with regard to the relative areas of the two valves thatthe second valve cannotopen untilthe scavengingair from the firstreservoir has passed into the cylinder. A graduated charge of heavy orlight oil vapor is then admitted to the cylininder through the secondvalve.

My invention also consists in a double-act ing two-stroke-cycleoil-vaporengine in which my scavenging arrangements are applied.

In the accompanyingsix sheets ofdrawings, Figure 1 is a sectionalelevation of a singleacting engine constructed according to my inventionand suitable for propulsive purposes. Figs. 2 and 3, Sheets 2 and 3,represent in plan a complete double-acting engine constructed inaccordance with the invention. Figs. 4 and 5, Sheets 4 and 5, show acentral longitudinal section of the engine, the displacer-pistonappearing in both figures for the sake of clearness. Fig. 6 is a partialVertical section ot Fig. 3 on the line :c fc. Fig. 7 is a crosssectionof Fig. 5 on the lines y y and .e

Referring to Fig. 1, upon the front end of the motor-cylinder l I form adisplacer-cyL inder 2, and I lit the motor-piston 3 with a trunkdisplacer-piston 4, which works within the cylinder 2. To thisdisplacer-piston I attach the usual connecting-rod 4, which drives tonto two iiy-wheel disks secured to the powershaft 7, only one of thedisks 6 being shown in Fig. 1, and works within a closed casing 8,formed as an extension of the displacer-cylinder. The space 9 behind thedisplacer-pistou is isolated from the motor-cylinder by the piston 3 andis in free communication with the atmosphere through the openings 10. Imay in some cases omit the separate displacerpiston 4 and utilize thefront of the piston 3 as displacer by making the clearance volume infront of the piston 3 sufficiently small. The displacer-piston on itsbackward stroke draws in a charge of air through the non-return valve1l, iitted in the side of the crank-chamber, and upon its forward strokeexpels a portion ofthe air charge through the non-return valve 12 intoan air-reservoir 13, the remainder of the charge passing to thevaporizer 28 through the flap-valve 14 and the vaporizer-valve 15, whereit takes up the oil charge which enters by the pipe 55. The passage 17,which leads from the vaporizer, is fitted with a throttle-valve 18 andcommunicates with a chamber 19 on the upper side of a spring-controlledvalve 20, which chamber is formed upon the motorcylinder cover. Thechamber beneath the valve 2O communicates by a passage 21 with theair-reservoir 13 and opens into the motor-cylinder through aspring-controlled valve 22, the stem 23 of which passes centrally upthrough the hollow stem 24 of the valve 20. Exhaust-ports 25 are formedin the walls of the motor-cylinder and are arranged so that they arecompletely uncovered when the motor-piston has reached the end of itsworking stroke. When this takes place, the pressure in the cylinder hasfallen sufficiently to allow the valve 22 to open under the pressure ofthe charge of air stored in the reservoir 13, which overcomes the forceof the spring 2 A quantity of air then rushes through the cylinder, thusthoroughly scavenging out the exhaust products. The spring 27 is soproportioned to the relative areas of the two valves that the valve 20cannot open until lthe scavenging-air from the reservoir 13 has passedinto the cylinder. The fall of pressure then permitsthe valve 20 to openand discharge the mixture of air and vaporized oil from the vaporizerinto the cylinder. Compression of the charge is then effected by thepiston 3 on its return stroke, the valves 2O and 22 closing under theincreased pressure andthe displacer-piston -L at thesame time drawing ina charge of air through the valve 11. When the motor-piston reaches theend of its stroke, ignition is effected by an electric spark whichpasses between the contactpoint-s 29 and 30 of the ignition-plug 3l, andthe cycle of operation is repeated. The exhaust products are conductedaway by a pipe 32 and utilized to vaporize the oil by passing themthrough a casting 33, which is united to the vaporizer 28 by aheat-conducting web 34. The vaporizer is tted with internal ribs 35,which are provided in order to canse thorough mingling of the air andoil charge and also to increase the internal heat-transmitting snrface,and wire-gauze or other suitable material is arranged interleaving theribs 35, as indicated by the dotted lines, so as to insure thoroughdivision of the oil-vapor.

Referring now to Figs. 2 to 7, inclusive, which illustrate adouble-acting engine constructed according to my invention, adoubleacting air-pump cylinder is secured to the front end of awater-jacketed motor-cylinder Gl. The piston 62 of the motor-cylinder ismade of considerable length, but hollowed on both sides, the projectingparts 63 63 on both sides being made of very thin metal closely fittingthe cylinder, so that the piston is sufciently cooled by thecylinder-walls without internal water circulation. Pistonrings 64E areplaced at the thickened central part 65 of the piston. This piston is ofsuch a length that exhaust-ports 8O:L in the center of the cylinder arefully opened when said piston has completed either a forward or abackward stroke. Between the motor and airpump cylinders I provide awater-cooled stuffing-gland 66, having suitable packing 67 on the end ofthe gland on the air-pump cylinder side. Fixed to the piston 62 andsliding within the stufng-gland 66 is a piston-rod 68, to which is alsosecured an air-pump piston 69. The rod 68 is carried through a gland'70a in the forward cover of the air-pump and is guided by means of atrunk-guide 7l. A connecting-rod 72 connects the guide 7l with thepower-shaft 7 2, which is inclosed by a casing 70. The air-pump cylinder60 has at its forward end an ai r-suction valve 74 and a nonreturnair-delivery valve 75 diametrically oppositeeach other. Correspondingvalves 76 and 77 are placed at the other end of the pump. (See Figs. 3and 7.) The deliveryvalves 75 and 77 are connected to a reservoir 78,supported above the motor-cylinder, but a little on one side of itsvertical axis. Formed on each lend of the motor-cylinder and leading toports 8l and 82 are chambers 79 and 80, containing spring-controlledvalves similar to those used in my single-acting engine. When a forwardstroke takes place, the air-pump piston 69 displaces air into thereservoir 7 8 through the pipe 87 ,some of which air will pass, by meansof a pipe 83 and Hapvalve 84, into a second reservoir 85. Asmall pipe 86from an oil-vaporizer conducts oil or vapor into the pipe 83, whenceit-is carried by the air into the reservoir 85. When the piston 62uncovers the ports 80, the exhaust-gases in the rear portion of thecylinder pass out through these ports. The pressure there then becomingreduced,the spring-controlled valve 88 opens, causing compressed airfrom the reservoir 78 to iiush the cylinder. Since this air expandswithin the cylinder, its pressure also becomes less, permitting thespring-controlled valve 89 to open, whereby explosive mixture from thereservoir 85 is admitted to the-rear of the cylinder. Pieces ofwire-gauze may be stretched across the passages 93 and 94, Figs. 3 and7, which lead from the reservoir 85 to the cylinder, to prevent ringback when ignition of the charge takes place in the latter. As thepiston 62 performs its return stroke compression of the newly-admittedcharge and ignition thereof takes place by means of the ignition-plug 8lin the rear end of the cylinder, While the cycle of operations justdescribed is commenced in the front end of the cylinder. Thus anexplosion takes place at each end of the cylinder every revolution ofthe engine, the exhaust-gases being in each case expelled by compressedair and replaced by a new charge.

Having now described my invention, what I claim as new, and desire tosecure by Letters Patent, is-

l. In an internal-combustion engine of the two-stroke-cycle type havingan air-displacer discharging into two reservoirs communicating with achamber connected to the enginecylinder through openings situated aboveeach other, a valve controlling the passage from the upper opening ofthe chamber, above a second valve controlling the passage from the loweropening to the engine-cylinder, the upper valve having a hollow stem,and guiding the lower valve, substantially as described.

2. Adouble-actinginternal-combustionengine of the two-'stroke-cycle typehaving a doubleacting air-pu mp delivering into a IOO IIO

In witness whereof I have hereunto set my hand in presence of twowitnesses.

I l y CHARLES ERNEST DAWSON.

Wtnes-ses:

BERTRAM H. I. MATTHEWS, GEORGE I. BRIDGES.

